Portable electronic devices, such as mobile phones, PDAs, DVCs and DSCs, are gaining increasing sophistication in functions and features. And to be accepted by the market, they have to be smaller in size and lighter in weight, and for the realization thereof, there is a growing demand for highly-integrated system LSIs. On the other hand, these electronic devices are desired to be easier or handier to use, and therefore the LSIs used in those devices are required to be more functionally sophisticated and better performing. For this reason, the higher integration of LSI chips is causing increases in I/O count (the number of inputs/outputs), which in turn generates demand for smaller packages. To satisfy both these requirements, it is strongly desired that semiconductor packages suited for the high board density packaging of semiconductor components be developed. To meet such needs, a variety of packaging technologies called CSP (Chip Size Package) are being developed.
Patent Document 1 discloses a semiconductor module where a semiconductor chip is mounted on an interposer board and this semiconductor is sealed by a sealing resin.